NTK ID0050 Ignition Knock -Detonation- Sensor

The ignition knock sensor determines if engine knock is present (caused by detonation). A piezoelectric crystal, which generates a varying voltage based upon engine vibration intensity, sends a signal to the ECM. The signal is used to retard ignition timing which prevents engine damage caused by pre-ignition. Located on the engine block, common causes for replacement include check engine lamp illumination, engine hesitation, poor fuel economy and failed emissions tests.